1. Technical Field
The present disclosure relates to headphones and, particularly, to a carbon nanotube based headphone.
2. Description of Related Art
Conventional headphone generally includes a headphone housing and an sound wave generator disposed in the headphone housing. The headphones can be categorized by shape into ear-cup (or on-ear) type headphones, earphones, ear-hanging headphones, and so on. The earphones can be disposed in one's ears. The ear-cup type headphones and ear-hanging headphones are disposed outside and attached to one's ears. The ear-cup type headphones have circular or ellipsoid ear-pads that completely surround the ears. The ear-hanging type headphones have ear-pads that sit on top of the ears, rather than around them. The headphones can also be categorized as wired headphones and wireless headphones.
The headphone housing generally is a plastic or resin shell structure defining a hollow space therein. The sound wave generator inside the headphone housing is used to transform an electrical signal into sound pressure that can be heard by human ears. There are different types of sound wave generators that can be categorized according by their working principle, such as electro-dynamic sound wave generators, electromagnetic sound wave generators, electrostatic sound wave generators and piezoelectric sound wave generators. However, all the various types ultimately use mechanical vibration to produce sound waves and rely on “electro-mechanical-acoustic” conversion. Among the various types, the electro-dynamic sound wave generators are most widely used.
Referring to FIG. 16, a related earphone 10, according to the prior art, with an electro-dynamic sound wave generator 100 is shown. The earphone 10 typically includes a housing 110. The sound wave generator 100 is disposed in the housing 110. The sound wave generator 100 includes a voice coil 102, a magnet 104 and a cone 106. The voice coil 102 is an electrical conductor, and is placed in the magnetic field of the magnet 104. By applying an electrical current to the voice coil 102, a mechanical vibration of the cone 106 is produced due to the interaction between the electromagnetic field produced by the voice coil 102 and the magnetic field of the magnets 104, thus producing sound waves. However, the structure of the electric-powered sound wave generator 100 is dependent on magnetic fields and often weighty magnets.
Carbon nanotubes (CNT) are a novel carbonaceous material and have received a great deal of interest since the early 1990s. Carbon nanotubes have interesting and potentially useful electrical and mechanical properties, and have been widely used in a plurality of fields.
What is needed, therefore, is to provide a headphone having a simple lightweight structure.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate at least one exemplary embodiment of the present headphone, in at least one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.